The invention relates to a propelling head for the pneumatic propelling of a multifilament tow, preferably consisting of endless fibres, the head comprising a housing constructed with a venturi portion and having a rear tow entrance end, a front tow exit end, at least one intermediate compressed air inlet conduit, and a centrally arranged through passage for the tow, the through passage extending centrally from the rear end to the front end, the air being conducted from the compressed air inlet conduit into the through passage.
In a known propelling head of this kind the compressed air is conducted from the inlet port to a tube provided at the tow exit end along the inner peripheral wall of the through passage, the tube being provided with a number of air outlet holes directed towards the tow exit end, the air jets or flows thereby produced propelling the multifilament tow by exerting thereon a propelling force in the direction towards the tow exit end, where the venturi portion of the housing serves to guide the flow of air towards the surface of the tow present in the through passage.